1. Field of the Invention
The present invention relates to an audio signal processor and generator. More specifically, the present invention relates to an audio signal processor and generator including a dynamic volume control system.
2. Description of the Related Art
Signal processors typically operate by changing various characteristics of a signal. For example, an audio signal processor may include a graphic equalizer or a parametric equalizer to improve the quality of a sound signal. The graphic equalizer and parametric equalizer control the gain of audio signals in selected frequency bands to subjectively improve the generated sound. Often the graphic equalizer and parametric equalizer boost the gain.
One problem that occurs in signal processors in an audio processing system is the possibility of overflow of the signal. If a full-scale input signal is applied to an audio processor and a system user requests a boost in gain of the signal, then the output signal generated by the audio processor exceeds full scale. Typically, the audio signal processor does not have a sufficient digital (bit) capacity to handle the boosted signal, resulting in signal errors such as overflow including clipping or wrapping of a signed signal to the opposite sign. Signal clipping and overflow are highly disadvantageous in processing of audio signals.
For example, clipping of a signal in the form of a sine wave creates multiple harmonic signals, distorting the frequency information of the signal, canceling the amplitude information in the signal, and creating distortion in the resulting sound signal.
What is needed is an audio processor that avoids signal distortion, clipping, overflow and wrapping.